Based On Sdh / Hfc Network High-speed Data Broadcasting System And Applied Research

As one of the information industry platforms CATV (Cable TV) has colossal network architecture in China. We face a challenge of how to exploit the existing network resource and network band to implement high-speed data transport.By adopting QAM (Quadrature Amplitude Modulation) modulation, we have researched and implemented a high-speed data broadcasting system compatible with DVB (Digital Video Broadcasting) standard in the past years, and integrated and applicated the system into SDH/HFC (Synchronous Digital Hierarchy/Hybrid Fiber Coax) network for the first time in China. In the system, information resources are collected and organized by variable requirements of users and data is broadcasted through channels and stored in personal computers so that users can select information in near interaction mode on demand.The high-speed data broadcasting system is compatible with almost all existing standard CATV equipments and can be applicated to networks including the national state or the 1ocal without changing the existing network. It supports 32Mbps of data rate in an 8MHz television channel, and provides functions of assigning band via channel and sub-channel, adjusting program transfer rate by software. In the system, a practical user authorization and program managing function, a flexible charge and band assigning mechanism, a dynamic program transfer policy are provided for the service provider of CATV. A dynamic program receiver policy is provided for users of CATV. A simple interface is provided for the third-party application software.In this thesis, principles of data coding for transferring data among different network hierarchies is described, a channel and program management center and a user authorization center are designed, and the integration and application of the system into SDH/HFC network are investigated and implemented.This thesis is divided into seven chapters. Chapter 1 deals with the background of the project and dada broadcast technology and its current status. Chapter 2 is concerned with the basic theory involved in the project. In chapter 3, principles and application requirements of high-speed data broadcasting system are described. Chapter 4 details data coding rule and efficiency. In chapter 3, the design and implementation of the management system is discussed. Chapter 6 expounds integration and application of high-speed data broadcasting system in SDH/HFC network. The conclusions of this thesis and furture research in the project are pointing in the end.